added auth service to go backend

backend-go/internal/domain/app_error/error_codes.go

@@ -5,16 +5,17 @@ type ErrorCode string
 
 const (
 	// General errors
-	InternalError      ErrorCode = "internal_error"
-	ValidationError    ErrorCode = "validation_error"
-	NotFoundError      ErrorCode = "not_found"
-	UnauthorizedError  ErrorCode = "unauthorized"
-	ForbiddenError     ErrorCode = "forbidden"
-	ConflictError      ErrorCode = "conflict"
-	DatabaseError      ErrorCode = "database_error"
+	InternalError        ErrorCode = "internal_error"
+	ValidationError      ErrorCode = "validation_error"
+	NotFoundError        ErrorCode = "not_found"
+	UnauthorizedError    ErrorCode = "unauthorized"
+	ForbiddenError       ErrorCode = "forbidden"
+	ConflictError        ErrorCode = "conflict"
+	DatabaseError        ErrorCode = "database_error"
 	ExternalServiceError ErrorCode = "external_service_error"
+	AuthError            ErrorCode = "auth_error"
 
 	// Specific errors
-	UserNotFoundError   ErrorCode = "user_not_found"
+	UserNotFoundError    ErrorCode = "user_not_found"
 	ProjectNotFoundError ErrorCode = "project_not_found"
 )

backend-go/internal/domain/app_error/helpers.go

@@ -23,3 +23,8 @@ func NewUnauthorizedError(message string) *AppError {
 func NewInternalError(err error) *AppError {
 	return Wrap(err, InternalError, "An internal server error occurred", http.StatusInternalServerError)
 }
+
+// NewAuthError creates an authentication error.
+func NewAuthError(message string) *AppError {
+	return New(AuthError, message, http.StatusUnauthorized)
+}

backend-go/internal/domain/repository/auth_repository.go

@@ -0,0 +1,13 @@
+package repository
+
+import (
+	"context"
+
+	E "github.com/IBM/fp-go/either"
+)
+
+type AuthRepository interface {
+	GenerateToken(ctx context.Context) func(userID string) E.Either[error, string]
+	ValidateToken(ctx context.Context) func(userID string) E.Either[error, string]
+	RevokeToken(ctx context.Context) func(userID string) E.Either[error, string]
+}